7-[2-[4-(6-Fluoro-3-methyl-1,2-benzisoxazol-5-yl)-1-piperazinyl]ethyl]-2-(1-propynyl)-7H-pyrazolo-[4,3-e]-[1,2,4]-triazolo[1,5-c]pyrimidin-5-amine (the compound of Formula I) is an adenosine A2a receptor antagonist useful in the treatment of central nervous system disorders including movement disorders, e.g., Parkinson's Disease, Extra-Pyramidal Syndrome, restless legs syndrome, essential tremor and Huntington's Disease; attention disorders, e.g., attention deficit hyperactivity disorder, cognitive impairment and negative symptoms of schizophrenia; and to other central nervous system diseases such as depression, stroke and psychoses. U.S. Pat. No. 6,897,217 and US 2007/0072867, the disclosures of which are herein incorporated by reference, relate to the compound of Formula I generically and specifically, respectively.
U.S. Pat. No. 6,897,217 discloses three general methods for preparing 2-alkynyl-substituted 5-amino-pyrazolo[4,3-e]-1,2,4-triazolo-[1,5-c]pyrimidines shown in the following Schemes A to C. A specific method for preparing the compound of Formula I disclosed in US 2007/0072867 is shown in Scheme D.




Processes for preparing 5-amino-pyrazolo-[4,3-e]-1,2,4-triazolo[1,5-c]pyrimidines substituted at the 2-position by, for example, a furanyl group are disclosed in U.S. Pat. No. 6,630,475 and U.S. Pat. No. 7,223,861.